1. Field of the Invention
The present invention relates to zero-force plug connector for a printed circuit board. The system includes a mechanism by means of which the printed circuit board zero-force plug connector can be changed from a fitting position, which allows the insertion or removal of a printed circuit board to a connected position, which makes contact correctly with the printed circuit boards, and vice versa.
Printed circuit board zero-force plug connectors are used to connect two printed circuit boards to one another electrically and mechanically substantially without the application of any force. They are used, inter alia, in order to allow a first printed circuit boards to be plugged easily and safely, and essentially at right angles, onto a second printed circuit boards (for example a so-called backplane motherboard) and, in the process to connect the first printed circuit boards electrically and mechanically to the second printed circuit boards, firmly and reliably.
Printed circuit board zero-force plug connectors have been known for quite some long time and have become known in a wide range of embodiments. A printed circuit board zero-force plug connector of the above-mentioned type is described, for example, in U.S. Pat. No. 3,130,351 to Giel.
The printed circuit board zero-force plug connector described in that prior art document is permanently mounted on one of the printed circuit boards which are to be connected to one another. The other of the printed circuit boards which are to be connected to one another can be inserted into the connector. It is constructed such that, by pulling on an operating member which is provided on the printed circuit board to be inserted and is designed essentially in the form of a rod, it can be changed to a fitting position which allows the insertion or removal of a printed circuit board, and can be moved into the connected position by the insertion of a printed circuit board.
The use of such and other printed circuit board zero-force plug connectors requires that they be handled carefully and exactly in accordance with the instructions. If, for example, an attempt is made to insert a printed circuit board into a printed circuit board zero-force plug connector which is in the connected position, or an attempt is made to remove such a printed circuit board from the connector when it is in this position, then this can easily lead to damage to the printed circuit board and/or to the printed circuit board zero-force plug connector. If, on the other hand, the printed circuit board zero-force plug connector is changed to the connected position when a printed circuit board has not been inserted in accordance with the instructions, then it is possible that no correct contact will be made between the printed circuit boards which are to be connected. Both of these situations are, of course, undesirable.
A further disadvantage of printed circuit board zero-force plug connectors of that type and similar devices is that they can be operated and used correctly only when the operating members provided on the printed circuit board are arranged and dimensioned exactly in accordance with the instructions (in a relative position with respect to the printed circuit board zero-force plug connector in accordance with the instructions). Discrepancies lead virtually inevitably to the operating member (for example the operating rod in the Giel patent) and the printed circuit board zero-force plug connector not engaging correctly when the printed circuit board is in the correct position, and/or to the operating element or the printed circuit board zero-force plug connector making it harder for the printed circuit board to assume the correct position, or making this impossible.